Vector to the Heavens
by Seito
Summary: "Welcome to Dive to the Heart." Destiny Islands was a strange and wondrous place. Aqua arrives in Destiny Islands just minutes before midnight. As the clock ticks down, the Dark Hour begins and she finds herself surrounded by Heartless and no way to defend herself. Persona 3 Fusion


I joined KH Secret Santa this year. I had key-of-destiny. I hope you enjoy the story!

This is a Persona 3 Fusion story. KH universe with Persona 3 elements. I don't know know that much about Persona 3 (OTL never finished the game), so I hope I got the elements right!

* * *

" _Welcome to Dive to the Heart."_

Destiny Islands was a strange and wondrous place. At its core, it was a small island chain that held a surprising amount of people. The local kids had their own small island to play on; a jungle gym of ramps, caves and docks. Sunshine, clear ocean water, and warm sand, the kids let their imagination grow and flourish.

" _This place exists between dream and reality, mind and matter."_

However, there was something strange about Destiny Islands. "Castle Oblivion," they whispered. "A white castle that grows on the kids' island." No one knew where it came from or why it appeared. Most thought it was a legend, a myth.

Few knew the truth.

" _Power sleeps within you. If you give it form… It will give you strength."_

Aqua stepped off the last ferry to Destiny Island. Terra had invited her to see his hometown. It had been some time since she saw her friend and classmate. Not since they parted ways from Master Erauqs' class. She was in need of a break so this was well deserved vacation.

" _Choose well."_

* * *

Aqua pulled out her phone, checking the time. 11:58 pm. Almost midnight. She hadn't expected to arrive so late, but there had been so many delays. It was a good thing she was able to catch the last ferry, otherwise she would have been stuck on the last island. With any luck though, Terra would be still be awake. She had no clue where the nearest inn was.

-Ping-

The clock struck midnight.

Aqua looked up from the text message she had been writing to Terra, startled by the sudden silence that descended. It was midnight, sure. But there were still a few people around. Even then it shouldn't descend into absolute silence, from the whirls of machines to the flickering of lights.

She paled as she noticed the appearances of coffins. Where had the coffins come from? What happened to the man behind the counter?

Aqua turned, hearing something in the distance. A wiggle, like something growing in the darkness. She took a step back when she saw the _yellow eyes_.

"Who's there?" she called out.

From the shadows stepped a small creature. It looked harmless, but a sense of dread overcame Aqua. It was small, like a dog, crawling and slithering along the floor like a snake or a bug. It had round beady yellow eyes and was jet black.

"What are you?" Aqua asked. Her eyes darted back and forth, recognizing the alarming number of yellow eyes that started to blink into existence around her. What was going on?!

The creature swarmed forward and Aqua turned and ran.

She darted through the empty streets, dodging the random coffins that had been placed around the dark streets. The street lights flickered and the night looked a sickly green. The full moon hung in the sky, ominous and looming.

She turned the corner just in time to see an even bigger creature towering in front of her. It looked like a twisted form of a giant, with large hands and wild hair strands. A gaping heart shaped hole was in its stomach. Aqua froze in terror, unable to comprehend what was happening. The creature rumbled, swinging its hand down towards her.

"Watch out!"

Someone grabbed her, pulling to the side.

Aqua looked, confused by the appearance of a silver haired teen. His aquamarine eyes stared unwaveringly at the dark creatures and he held in his hand a strange shaped sword. It was curved like a bat wing, a dark purple and red color. A single white wing protruded from the top of the sword.

"A Darkside huh?" the teen said.

He turned his sword around and pierced his heart. "Come Ansem!"

"I am thou. Thou art me. I am come from the seas of thy heart. The Seeker of Darkness, Ansem!"

Aqua stared as a man materialized in the air. Dark skin and long white hair, there was an eeriness to him that told Aqua he wasn't quite human. She shivered as a gust of breeze seem to blow, causing the man's white and black trench coat to flutter.

She didn't get a chance to further observe him before the silver haired teen whisked her off her feet and away from the battle.

" _Now step forward. Can you do it?"_

"Are you alright?" the silver haired teen asked her. They came to a stop several blocks away. It was empty, no sign of the yellow eyes anywhere.

"No!" Aqua snapped, unable to keep the shrill out of her voice. "What is going on here?"

The silver haired teen took a deep breath. "Okay. First, I'm Riku. Hi."

"Aqua," Aqua introduced herself.

"Terra's friend?" Riku asked, surprised.

"You know him?" Aqua couldn't help but ask.

Riku nodded. "Yeah. He mentioned you were coming to visit. Sorry that you had to get wrapped up in all of this."

"What is this exactly?" Aqua asked. She could feel the hysteria creeping into her voice. Normally she wouldn't be this shaken, but given the night she was having, she felt she was well justified.

"Look," Riku said. "These creatures you see? They're called Heartless. They come out what we've been calling the 'Dark Hour'; the 25th hour of the day. The Heartless prey on people's hearts. Most people are protected by the coffin they subconsciously form, but not everyone is lucky and they have their heart stolen."

He held out his strange sword. "This is called a Keyblade. They're the only weapons that can hurt the Heartless. They are also the key to summoning what is called a Persona."

"Persona? Is that the man you summoned?" Aqua asked.

" _Keep your light burning strong."_

Riku nodded. "Yeah, that was Ansem, Seeker of Darkness. But there are many different ones." He checked the time on his phone. "Look, we got 20 minutes before the Dark Hour is over. Just stick close and I'll explain more later."

-Clang!-

Aqua stared up in horror as an armored Heartless dropped in front of them. It looked like a disjointed knight, arms and legs floating separately from its lilac purple body. "What is that!" she asked.

" _The closer you get to the light, the greater your shadow becomes."_

"A Guard Armor," Riku said. "What is it doing here?!"

The Guard Armor jumped, crashing down and causing a shockwave that sent Riku and Aqua skidding down the street. Riku grabbed Aqua's hand and ran down the street. It chased after them. Riku grabbed Aqua, jumping to evade the spinning gauntlet.

" _But don't be afraid."_

"Che," Riku said, as another Guard Armor appeared in front of them.

"Why are there so many?" Aqua asked. This was not what she was expecting when she came to Destiny Island. Why the hell didn't Terra warn her? She could have at least brought a weapon or something with her!

" _And don't forget… "_

Riku lifted his Keyblade above his head. "Look, we're not that far from Terra's place. Think you can make a run for it? We use his place as a headquarters. Someone should be there. They can protect you."

"I can't leave you behind!" Aqua protested.

"I can't protect you and fight against these Guard Armors at the same time," Riku said. "Head straight for two blocks, then make a right. It's the yellow house."

"But…"

"Go!"

" _But don't be afraid."_

Aqua ran. If she made to Terra's house, then whoever was there, she could send out to help Riku. She ran down the two blocks, evading the swipes from the smaller heartless. Aqua vaulted over a car, sliding down the back window and jumping off from the trunk to evade another two small Heartless. Just as she turned the corner another Guard Armor dropped down in front of her.

"Agh!" Aqua skidded across the street. She struggled to her feet as the Guard Armor approached her. Her skin was rubbed raw, bleeding from being thrown around all over the place. She rolled away as one of the feet hammered towards her. Aqua gave a quick survey of her injuries before her eyes hardened with determination. She would not give up.

" _You hold the mightiest weapon of all."_

As if guided by an invisible force, Aqua placed her hand over her heart and took a deep breath. The world seemed to slow down, quieting for a brief second. A flicker of light began to pulse. Aqua pulled her hand away from her chest, a shower of sparks appearing before materializing into Keyblade.

She paused to inspect it in awe. It had a dull metallic blue color body, accented with silver. Its head was diamonded shape though one point was missing, with silver spikes for teeth. The guard was white and its handle a smooth black.

"Rainfell," Aqua said, the name falling from her lips.

Her eyes narrowed as she dodged a body spin attack from the Guard Armor. She blocked the gauntlets that followed afterward.

Instinctively, she turned Rainfell around. In one swift moment, she pierced her heart. "Persona!"

-Crack-

The boundaries of reality seemed to shatter as a young girl with short black hair began to materialize. She was dressed in a black coat with a silver chain.

"I am thou. Thou art me. I am come from the seas of thy heart. I am Xion, Vector to the Heavens!"

Aqua stared. This was her Persona?

Xion smiled. The Guard Armor flung itself at her only to be stopped by a barrier. Xion raised her hand up in the air. "Event Horizon," she said, dropping her hand.

The last thing Aqua remembered was her shielding her eyes as four beams of light appeared, exploding outward.

" _So don't forget:"_

* * *

Aqua woke to an unfamiliar ceiling and a soft bed. Her body throbbed and ached as her mind spun, trying to piece together how she had gotten here. Unbidden, the memories of the night, the Heartless, Persona and Riku floated forward. What is all a dream?

"Hey."

She turned to see Terra sitting in the chair next to the bed. "How are you feeling?" Terra asked.

Aqua sighed. "Tired, sore," she answered honestly. "Do Heartless mean anything to you, Terra?"

She watched as her friend flinched. "So not a dream," Aqua mumbled, sitting up. She struggled with the cotton blanket. "Is Riku okay?"

"Take it easy," Terra said, helping her. "Summoning your Persona for the first time is always tiring. And yes Riku is fine."

Aqua closed her eyes. "Now what?" she asked.

"Whatever you want," Terra answered.

Aqua stared out the window. The scene outside was peaceful, nothing like last night where there had been monsters roaming the streets. It was disconcerting that outside was just bright blue skies, white clouds and happy people. There was obviously a mystery that needed solving. She had the power to do something about it.

If she walked away, who knew who else would have to take up her spot. Unacceptable.

"I want to help."

 _You are the one who will open the door._

* * *

Happy Holidays! _  
_


End file.
